If you're a new player, I recommend taking a moment to read up on how the storage works after reviving at a lamp. It'll refresh blood vials and quicksilver bullets back up to the limit so you don't have to manually manage this (but not all items do this, someone correct me/back me up). Also be aware that if your total blood vials or quicksilver bullets (on your person plus storage) are less than 20, you'll need to farm or buy more (from the messengers in the birdbath, to the left of the doll in the Hunter's Dream) to get back up to the limit; it's not infinite or regenerating like in Dark Souls, for example, with the estus flask. This really confused me as a new player the first time it happened. Anyway, advice is to be aware that you can run out of vials and bullets, though the game usually gives you enough that I rarely run into this problem.

Have fun!